Protein Tagging of GPCR

Protein Tagging of GPCR

For Research Use Only. Not For Clinical Use.

CD BioSciences provides high-quality protein tagging services for both GPCR research and pharmaceutical use. Our experienced scientists can help our customers choose protein tags that are right for their experiments and downstream applications.

Introduction of Protein Tagging

Protein tagging is an important aspect of protein analysis, which commonly refers to the fusion expression of a polypeptide or protein with target protein using recombinant DNA technology. A variety of protein tags with different functions have been successively developed and applied in various applications. Most protein tags can be used for protein expression, purification, detection and tracking using such techniques as immunoassays, pull-down assays, Western blotting and ELISA. Certain tags may be used for subcellular localization, protein interaction and functional study.

G protein-coupled receptors (GPCRs), the largest class of membrane proteins in the human genome, are highly relevant to various diseases. GPCR research has always been the forefront and center of drug development and precision medicine. Protein tagging can facilitate a wide variety of studies on their structure and function. However, the nature of the protein tag and its location within the receptor need to be considered carefully.

Figure 1. Some potential applications of epitope-tagging. (Huang Y & Willars G B., 2011)Figure 1. Some potential applications of epitope-tagging. (Huang Y & Willars G B., 2011)

Overview of Protein Tags

Explore the options below. We can choose the best tag for your specific application.

Category Description
Affinity tags Affinity tags added to either the N-terminal or C-terminal of the target protein can facilitate purification from its original biological source using affinity techniques.
Solubilization tags Solubilization tags can be used to assist in proper folding of proteins and keep them from precipitating.
Chromatography tags Chromatography tags can be used to alter chromatographic properties of target proteins. Different resolution can be afforded by particular separation technique.
Epitope tags Epitope tags refers to small antigenic peptides usually derived from viral genes with high-affinity to antibodies. These tags are applicable for protein purification, protein expression and subcellular localization.
Fluorescence tags Fluorescence tags can be used to realize visualization of target proteins. GFP and its variants are commonly used.

Commonly Used Protein Tags

Tags Sequence/Origin Tags Sequence/Origin
Poly-His- nH (n = 2-12, usually 6) CBP- KRRWKKNFIAVSAANRFKKI
GST- Glutathione-S-transferase Chitin-binding tag TNPGVSAWQVNTAYTAGQL
Poly-Arg- nR (n = 5-6, usually 5) HAT- KDHLIHNVHKEFHAHAHNK
Strep-tag WRHPQFGG GFP Aequorea victoria (26.9 kDa)
S- KETAAAKFERQHMDS Halo tag Rhodococcus (33 kDa)
MYC EQKLISEEDL NusA 495 amino acids
MBP AEEGKLVIW TrxA Escherichia coli. (12 kDa)
c-Myc EQKLISEEDL Fh8 Fasciola hepatica (8 kDa)
Avi- GLNDIFEAQKIEWHE SUMO 100 amino acids
Strep-tag II WSHPQFEK SNAP O6-alkylguanine-DNA-alkylransferase

CD BioSciences is always ready to provide the best services to each of our customers. We can help you choose the appropriate labeling strategies and offer the optimized protocols.

If you are interested in our services or have any specific requirements, please feel free to contact us for more details.


  1. Huang Y & Willars G B. Generation of epitope-tagged GPCRs. Receptor Signal Transduction Protocols. Humana Press, Totowa, NJ, 2011: 53-84.
  2. Lotze J, et al. Peptide-tags for site-specific protein labelling in vitro and in vivo. Molecular BioSystems, 2016, 12(6): 1731-1745.